He was sentenced to 10 years in prison for a robbery in San Juan but only served five months time before getting let out on a special form of probation.
Edgar Garces Diaz is now facing murder and attempted murder charges in Harlingen.
An Action 4 News investigation has revealed that Diaz was on probation at the time of the fatal April 1st shooting on Wright Street.
Court records show that Diaz was given shock probation for the robbery and was let out of prison early.
U.S. Customs and Border Protection (CBP) officers arrested the 22-year-old San Juan man on Sunday evening.
Diaz was the passenger in a car that arrived from Mexico at Brownsville TMs Veterans International Bridge.
The San Juan man is the third suspect arrested in the murder of 21-year-old Mayra Bianey Oyervides off of Wright Street in Harlingen.
Oyervides was killed when two gunmen were shooting and trying to kill her fiance TMs 18-year-old nephew Leonel Lee Garcia.
Court records show Diaz was identified as one of two gunmen captured by surveillance cameras at the scene.
The second gunman Margarito Garces Soto remains at large and is presumed to be in Mexico.
"No Food At Home"
An Action 4 News review of court records show that at the time of the Wright Street shooting, Garces was out on probation for a robbery in San Juan.
San Juan police originally arrested Diaz on an aggravated robbery charge back in August 2009.
Investigators reported that Diaz held up the Pocket Store at 600 North Veterans Boulevard at knifepoint.
Officers found him walking in the alleyway at the 500 block of West Athol Street where he was found with the stolen cash in his pockets.
Diaz gave San Juan police a full confession admitting to holding up the store due to economic hardships stating that he did not have any food at home.
But records show that the aggravated robbery charge was to reduced to the lesser crime of robbery in the court system.
Judge Rose Guerra Reyna with the 206th State District Court sent him to prison for 10 years in prison back in December 2009.
But Texas Department of Criminal Justice (TDCJ) records show Diaz was released from prison in April 2010.
Diaz's defense attorney Della Perez could not be reached for comment but records show she filed a motion for shock probation in January 2010.
Under Texas state law, people with no prior criminal history or a minor criminal history can qualify for shock probation.
Shock probation allows people convicted of and sentenced to prison for certain types of felonies to be released early and placed on probation for the remainder of their sentence.
Under state law, those seeking shock probation must make the request within the first six months of their sentence and demonstrate good behavior in prison.
Although aggravated robbery is not eligible for shock probation, robbery is eligible for it.
Court records show that Diaz did not appear to have a prior criminal history before being sentenced for robbery.
Action 4 News spoke to Hidalgo County District Attorney Rene Guerra about Diaz being given shock probation.
Guerra did not have details about the case but said shock probation is meant to rehabilitate eligible candidates.
The district attorney said many people have successfully complete shock probation.
Candidates must apply, qualify and receive a hearing in front of a judge, who decides whether or not to grant it.
We could not have known whether he would be a serious criminal, Guerra told Action 4 News.
Court records show that the Hidalgo County District Attorney's Office filed a motion to revoke Diaz TMs probation in June.
Judge Reyna responded by issuing an order for his arrest in July.
San Juan Police Chief Juan Gonzalez spoke to Action 4 News about the case.
Chief Gonzalez said all violent crimes are preventable.
The San Juan police chief said violent criminals will usually continue to commit more violent crimes if released early from prison.
"I feel this state should be like other states where mandatory sentences must be completed by violent offenders and any type of low sentencing or probation is not an option," Gonzalez said.